NSG 6440 DERMATOLOGICAL DISORDERS
QUESTIONS WITH ANSWER
Dermatological disorders Q-Bank Questions and Rationales
1. A patient with diabetes has right anterior shin edema, erythema, warmth,
and tenderness to touch. This developed over the past 3 days. There is no
visible pus. What is the most likely diagnosis to consider?
Deep vein thrombosis (DVT)
Buerger’s disease
Cellulitis Correct
Venous disease
Rationale:
This description is one of cellulitis. Cellulitis involves an infection of the
subcutaneous layers of the skin. It must be treated with an oral antibiotic.
In a patient with diabetes, it is particularly important to identify, and
aggressively treat cellulitis early, because elevated blood sugar levels will
make eradication more difficult. Buerger’s disease involves inflammation
of the medium-sized arteries and does not present on the anterior shin
only. DVT seldom presents on the anterior shin, so this is not likely.
Venous disease does not present acutely, as in this situation.
2. An example of a first-generation cephalosporin used to treat a skin
infection is:
cephalexin. Correct
cefuroxime.
cefdinir.
cefaclor.
Rationale:
Two common first-generation cephalosporins used to treat skin and skin
structure infections are cephalexin and cefadroxil. These are taken two to
, four times daily and are generally well tolerated. These antibiotics
provide coverage against Staphylococcus and Streptococcus, common
skin pathogens.
3. A patient reports that he found a tick on himself about 2 weeks ago. He
presents today with a red circle and a white center near where he
remembers the tick bite. He did not seek treatment at that time. Today he
complains of myalgias and arthralgias. Which laboratory test can be used
to help diagnose Lyme disease?
CBC
Lyme titer
ELISA Correct
Skin scraping
Explanation:
A detailed history should always precede testing for Lyme disease. The red
circle with the white center is likely erythema migrans (EM). EM is the
characteristic skin lesion of Lyme disease (and other illnesses) and usually
occurs within 1 month following the tick bite. Many learned authorities,
including the Infectious Diseases Society of America, conclude that
individuals should not be screened/tested for Lyme disease unless they have
a high probability of having Lyme disease. In this case, historical features
coupled with physical exam support the diagnosis, and thus screening. The
most common initial serologic test for screening is an ELISA. If it is
positive, it should be confirmed with a Western blot. Unfortunately, there
are a large number of false positives and so a confirmation should be
performed.
4. A 16-year-old male has nodulocystic acne. What might have the greatest
positive impact in managing his acne?
Retin-A plus minocycline
Benzoyl peroxide plus erythromycin
Isotretinoin (Accutane) Correct
QUESTIONS WITH ANSWER
Dermatological disorders Q-Bank Questions and Rationales
1. A patient with diabetes has right anterior shin edema, erythema, warmth,
and tenderness to touch. This developed over the past 3 days. There is no
visible pus. What is the most likely diagnosis to consider?
Deep vein thrombosis (DVT)
Buerger’s disease
Cellulitis Correct
Venous disease
Rationale:
This description is one of cellulitis. Cellulitis involves an infection of the
subcutaneous layers of the skin. It must be treated with an oral antibiotic.
In a patient with diabetes, it is particularly important to identify, and
aggressively treat cellulitis early, because elevated blood sugar levels will
make eradication more difficult. Buerger’s disease involves inflammation
of the medium-sized arteries and does not present on the anterior shin
only. DVT seldom presents on the anterior shin, so this is not likely.
Venous disease does not present acutely, as in this situation.
2. An example of a first-generation cephalosporin used to treat a skin
infection is:
cephalexin. Correct
cefuroxime.
cefdinir.
cefaclor.
Rationale:
Two common first-generation cephalosporins used to treat skin and skin
structure infections are cephalexin and cefadroxil. These are taken two to
, four times daily and are generally well tolerated. These antibiotics
provide coverage against Staphylococcus and Streptococcus, common
skin pathogens.
3. A patient reports that he found a tick on himself about 2 weeks ago. He
presents today with a red circle and a white center near where he
remembers the tick bite. He did not seek treatment at that time. Today he
complains of myalgias and arthralgias. Which laboratory test can be used
to help diagnose Lyme disease?
CBC
Lyme titer
ELISA Correct
Skin scraping
Explanation:
A detailed history should always precede testing for Lyme disease. The red
circle with the white center is likely erythema migrans (EM). EM is the
characteristic skin lesion of Lyme disease (and other illnesses) and usually
occurs within 1 month following the tick bite. Many learned authorities,
including the Infectious Diseases Society of America, conclude that
individuals should not be screened/tested for Lyme disease unless they have
a high probability of having Lyme disease. In this case, historical features
coupled with physical exam support the diagnosis, and thus screening. The
most common initial serologic test for screening is an ELISA. If it is
positive, it should be confirmed with a Western blot. Unfortunately, there
are a large number of false positives and so a confirmation should be
performed.
4. A 16-year-old male has nodulocystic acne. What might have the greatest
positive impact in managing his acne?
Retin-A plus minocycline
Benzoyl peroxide plus erythromycin
Isotretinoin (Accutane) Correct
